Management of Bronchial Stenosis and Bronchomalacia After Lung Transplantation: Conclusion

Most patients have significant improvements in symptoms and pulmonaiy functions after stent placement. Airway patency has been maintained with a single stent in four patients, while three patients required more than one stent. One of the concerns associated with metallic stents is that bronchial erosion, bleeding, and excessive granulation tissue may occur after placement. The Gianturco stent has been reported to cause fatal massive hemoptysis and spontaneous stent fracture. However, in our experience, no bronchial erosion, bleeding, or development of excessive granulation tissue has occurred after the placement of the Palmaz stent.
Because of the rigid structure of the deployed stent, it is not clear how much stress a Palmaz stent is capable of handling within the airway. The stent comes in a variety of lengths. The ultimate length after deployment depends on the final diameter the stent is expanded to—the larger the diameter, the shorter the stent becomes. It is presumed that its ability to withstand the centripetal forces generated by the changes in intrathoracic pressures associated with mechanics of breathing, coughing, and the Valsalva maneuver would also vary with different lengths and diameters. www.mycanadianpharmacy.com in detail During dynamic respiratory actions, radial compression of the stent inside the airway may decrease the diameter of the stent, thereby predisposing it to migration along the airway. Unlike the self-expandable metallic stent, Wall-stent (Pfizer; New York, NY), the Palmaz stent is not capable of springing back into its previously dilated diameter when such compression occurs. We have seen in our limited experience examples of partial stent dehiscence from the bronchial wall, partial obstruction of a bronchial lumen by the stent, stent migration (including one stent which was coughed up by the patient), and stent collapse. Data on how well the Palmaz stent is capable of withstanding intrathoracic pressure changes for prolonged time periods are lacking.
In conclusion, our experience with the balloon-expandable metallic (Palmaz) stent in the setting of posttransplant airway obstruction demonstrates the safety, the relative ease of placement using a flexible fiberoptic bronchoscope, and the potential removability of the stent. However, stent migration during and after placement, stent dehiscence from the bronchial wall, and stent collapse remain potential complications. Its future role in the management of airway obstruction in general, and bronchial obstruction in LT recipients in particular, should perhaps be best defined by a prospective multicenter comparative study with other metallic stents.

Category: Lung Transplantation

Tags: bronchial stenosis, bronchomalacia, lung transplant, stent